Modular Approach to Saturated and α,β-Unsaturated Ketones
摘要:
2-Fluoro-6-pyridinyloxy derivatives of 2-ethoxyvinyl carbinois react with radicals derived from xanthates by an addition fragmentation pathway to give highly functionalized ketones after acid hydrolysis. 1,4-Diketones are readily accessible by this approach. alpha,beta-Unsaturated ketones can be obtained by starting with geminal acetoxy xanthates prepared by addition of a simpler xanthate to vinyl acetate.
A Convergent Radical Based Route to Trifluoromethyl Ketones and to α,β-Unsaturated Trifluoromethyl Ketones
作者:Lucile Anthore、Samir Z. Zard
DOI:10.1021/acs.orglett.5b01344
日期:2015.6.19
A convergent synthesis of trifluoromethyl ketones and α,β-unsaturated trifluoromethyl ketones is described, starting with aliphatic iodides and dithiocarbonates (xanthates) and exploiting both the α- and β-fragmentations of a sulfonyl radical. The transformation initially furnishes the ketones in a masked enol carbonate form, from which they can be easily regenerated.
Visible light/Ir(III) photocatalytic initiation of xanthate-based radical-chain reactions: Xanthate group transfer and oxidative addition to aromatic systems
作者:Pedro López-Mendoza、John E. Díaz、Alix E. Loaiza、Luis D. Miranda
DOI:10.1016/j.tet.2018.04.079
日期:2018.9
The protocol can be used in classical xanthate-based inter- and intra-molecular group transfer reactions and oxidative radical addition to several heteroaromatic systems. The process does not require high temperature and reactions are cleaner compared with the traditional peroxide initiation. In the oxidative addition to aromatic systems, the oxidation process is part of the catalytic cycle and does